The latest clue to the feds' approach comes in a letter from Obama administration drug czar Gil Kerlikowske, in which he acknowledges that the country is "in the midst of a serious national conversation about marijuana."

The lion's share of Kerlikowske's letter -- prompted by the petitions reaching the 25,000 signature level quickly enough to trigger an automatic Obama administration response -- features quotes from the President's recent interview with Barbara Walters, in which he said individual users wouldn't be targeted while arguing against more universal legalization. But prior to citing the Justice Department's ongoing review of the Colorado and Washington measures, and alluding to the differences between federal law and those in the states in question, Kerlikowske writes, "Coming out of the recent election, it is clear that we're in the midst of a serious national conversation about marijuana."

This phrase strikes Tom Angell, chairman of the organization Marijuana Majority and a close follower of events in Colorado, as significant.

Continue for more about Kerlikowske's comments, including the entire letter and a video.

Tom Angell.

Here's Angell's take, shared via e-mail.

"I guess it makes a difference when marijuana legalization gets more votes than your boss does in an important swing state, as happened in Colorado this last election," Angell notes. "From 'legalization is not in my vocabulary and it's not in the president's,' as Gil Kerlikowske often used to say, to 'it is clear that we're in the midst of a serious national conversation about marijuana' is a pretty stark shift.

"Of course, what really matters is to what extent the administration actually shifts enforcement priorities and budgets," he acknowledges. "But I sure do like hearing the U.S. drug czar acknowledge the fact that marijuana legalization is a mainstream discussion that is happening whether he likes it or not."

Below, see Kerlikowske's letter, followed by excerpts from Obama's interview with Barbara Walters.

Addressing the Legalization of Marijuana

By Gil Kerlikowske

Thank you for participating in We the People and speaking out on the legalization of marijuana. Coming out of the recent election, it is clear that we're in the midst of a serious national conversation about marijuana.

At President Obama's request, the Justice Department is reviewing the legalization initiatives passed in Colorado and Washington, given differences between state and federal law. In the meantime, please see a recent interview with Barbara Walters in which President Obama addressed the legalization of marijuana.

Barbara Walters:

Do you think that marijuana should be legalized?

President Obama:

Well, I wouldn't go that far. But what I think is that, at this point, Washington and Colorado, you've seen the voters speak on this issue. And as it is, the federal government has a lot to do when it comes to criminal prosecutions. It does not make sense from a prioritization point of view for us to focus on recreational drug users in a state that has already said that under state law that's legal.

...this is a tough problem because Congress has not yet changed the law. I head up the executive branch; we're supposed to be carrying out laws. And so what we're going to need to have is a conversation about how do you reconcile a federal law that still says marijuana is a federal offense and state laws that say that it's legal.

When you're talking about drug kingpins, folks involved with violence, people are who are peddling hard drugs to our kids in our neighborhoods that are devastated, there is no doubt that we need to go after those folks hard...it makes sense for us to look at how we can make sure that our kids are discouraged from using drugs and engaging in substance abuse generally. There is more work we can do on the public health side and the treatment side.

Gil Kerlikowske is Director of the Office of National Drug Control Policy